Radiating package module for exothermic element

ABSTRACT

Disclosed herein is a radiating package module for an exothermic element. The radiating package module includes a heat conducting plate which has a groove of an internal thread shape, with the exothermic element being mounted on a surface of the heat conducting plate. A heat pipe is inserted into the groove in a screw-type coupling manner and has a coupling part of an external thread shape. An adhesive is applied between the groove and the coupling part. A cooling unit is coupled to an end of the heat pipe. The radiating package module maintains the reliability with which the radiating package radiates heat and improves structural reliability.

CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit of Korean Patent Application No. 10-2009-0078131, filed on Aug. 24, 2009, entitled “RADIATING PACKAGE MODULE IN EXOTHERMIC ELEMENT”, which is hereby incorporated by reference in its entirety into this application.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a radiating package module for an exothermic element.

2. Description of the Related Art

The quantity of light of a luminous element is very susceptible to the design of a radiating package. Considering that the luminous element emits in the form of heat about 60%˜80% of the power which is applied, the thermal design of the radiating package is very important in terms of luminous efficiency of the luminous element and thermal reliability. Also, in a package module on which an exothermic element as well as the luminous element is mounted, the efficiency of the module is considerably affected by the radiative ability of the designed radiating package module.

Generally, many of the radiating package module of the exothermic element use a forced air cooling method. A heat sink, a heat pipe, a fan, and a blower have been used as parts of the radiating package module.

A thermal interface material (TIM) is used between the package with the exothermic element and the heat sink so as to minimize thermal resistance generated in the empty space. In order to minimize thermal resistance between radiative parts in the radiating package module, the radiative parts are coupled to each other by applying solder paste or thermal grease to a coupling cooling part, thus improving heat transfer characteristics.

The conventional radiating package module generally includes an exothermic element, a heat conducting plate on which the exothermic element is mounted, a heat pipe which transfers emitted heat, and a cooling unit which radiates transferred heat to an outside.

In order to assemble the heat conducting plate having the exothermic element with the heat pipe, the heat pipe is forcibly fitted into the heat conducting plate, and thereafter is pressed using a press. Such a forcible fitting method impairs the surface of the heat pipe, so that water may leak out of the heat pipe in a reliability test. In the case where solder paste is used as an adhesive, a bonded state may become poor when the heat pipe and the heat conducting plate are coupled to each other in a reflow process.

Therefore, the radiating package module is problematic in that a crack may occur in a test for high temperature reliability, impact or vibration. Especially, a crack may occur between solder paste material and the heat pipe or between solder paste material and the heat conducting plate because of external vibration, so that thermal resistance increases at a contact surface, and thus the lifespan of the package may be reduced.

SUMMARY OF THE INVENTION

The present invention is intended to provide a radiating package module for an exothermic element which is capable of improving structural reliability by changing a coupling shape in place of a simple coupling method using solder paste or thermal grease.

Further, the present invention is intended to provide a radiating package module for an exothermic element, in which a groove of a heat conducting plate and a coupling part of a heat pipe have a thread shape and are coupled to each other in a screw-type coupling manner, micro patterns are provided on the groove of the heat conducting plate and a surface of the coupling part of the heat pipe, and a polymer core is added to solder paste or thermal grease, thus improving both the reliability of radiating heat and structural reliability.

In an exemplary radiating package module for an exothermic element according to an embodiment of the present invention, a heat conducting plate has a groove of an internal thread shape, with the exothermic element being mounted on a surface of the heat conducting plate. A heat pipe is inserted into the groove in a screw-type coupling manner and has a coupling part of an external thread shape. An adhesive is applied between the groove and the coupling part. A cooling unit is coupled to an end of the heat pipe.

The groove may pass from a side of the heat conducting plate to an opposite side thereof.

Further, the coupling part may have a shape of a round thread.

In an exemplary radiating package module for an exothermic element according to another embodiment of the present invention, a heat conducting plate has a groove of an internal thread shape, with the exothermic element being mounted on a surface of the heat conducting plate. A heat pipe is inserted into the groove in a screw-type coupling manner, and has a coupling part of an external thread shape. An adhesive is applied between the groove and the coupling part. A polymer core is contained in the adhesive. A cooling unit is coupled to an end of the heat pipe. Here, a micro pattern is formed on either of a surface of the groove or a surface of the coupling part.

Further, the micro pattern may be formed in the same direction as the thread.

In an exemplary radiating package module for an exothermic element according to a further embodiment of the present invention, a heat conducting plate has the exothermic element mounted on a surface thereof and a groove of an internal thread shape, with a first micro pattern being formed on a surface of the groove. A heat pipe is inserted into the groove in a screw-type coupling manner, and has a coupling part of an external thread shape, with a second micro pattern being formed on a surface of the coupling part. An adhesive is applied between the groove and the coupling part. A polymer core is contained in the adhesive. A cooling unit is coupled to an end of the heat pipe.

Further, each of the first and second micro patterns may be formed in the same direction as a thread and at corresponding positions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a radiating package module for an exothermic element according to a preferred embodiment of the present invention;

FIG. 2 is a sectional view taken along line A-A′ of FIG. 1 and illustrating a heat conducting plate according to the preferred embodiment of the present invention;

FIG. 3 is a perspective view illustrating a heat pipe according to the preferred embodiment of the present invention;

FIG. 4 is a sectional view taken along line A-A′ of FIG. 1 and illustrating a heat conducting plate according to another preferred embodiment of the present invention;

FIG. 5 is a perspective view illustrating a heat pipe according to another preferred embodiment of the present invention; and

FIG. 6 is a sectional view illustrating the coupled shape of a coupling part of a heat pipe with a groove of the heat conducting plate in a screw-type coupling manner according to the preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Various objects, advantages and features of the invention will become apparent from the following description of embodiments with reference to the accompanying drawings.

The terms and words used in the present specification and claims should not be interpreted as being limited to typical meanings or dictionary definitions, but should be interpreted as having meanings and concepts relevant to the technical scope of the present invention based on the rule according to which an inventor can appropriately define the concept of the terms to describe most appropriately the best method he or she knows for carrying out the invention.

The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings. Herein, the same reference numerals are used throughout the different drawings to designate the same components. Further, when it is determined that the detailed description of the known art related to the present invention might obscure the gist of the present invention, the detailed description thereof will be omitted.

Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view illustrating a radiating package module for an exothermic element according to a preferred embodiment of the present invention, FIG. 2 is a sectional view taken along line A-A′ of FIG. 1 and illustrating a heat conducting plate included in the radiating package module, and FIG. 3 is a perspective view illustrating a heat pipe which is to be coupled to a heat conducting plate in a screw-type coupling manner.

The radiating package module according to the preferred embodiment of the present invention will be described below with reference to FIG. 1.

The radiating package module according to this embodiment includes a heat conducting plate 20, a heat pipe 30, an adhesive, and a cooling unit 40. The heat conducting plate 20 has a groove, with an exothermic element 10 mounted to a surface of the heat conducting plate 20. The heat pipe 30 has a coupling part which is inserted into the groove to be coupled thereto in a screw-type coupling manner. The adhesive is applied between the groove and the coupling part. The cooling unit 40 is connected to an end of the heat pipe 30.

Here, the exothermic element 10 means an element which generates heat to the outside when the element is operated in combination with a luminous element. Particularly, the luminous element means an element which transforms electric energy into light energy. The luminous element may comprise an Integrated Circuit (IC) chip such as a Light Emitting Diode (LED) or an Injection Laser Diode (ILD). Compared to other luminous elements, the LED is inexpensive and may be operated within a wide temperature range, so that the LED may be widely used in a variety of fields. Recently, the LED has been widely used for illumination of cars as well as for general illumination.

Further, the exothermic element 10 is mounted on a surface of the heat conducting plate 20. The heat conducting plate 20 transmits heat from the exothermic element 10 to the heat pipe 30, in addition to locking and supporting the exothermic element 10.

The heat pipe 30 absorbs heat transmitted via the heat conducting plate 20, prior to transmitting the heat to the cooling unit 40. The heat transfer method of the heat pipe 30 is classified into two methods, the first of which involves the heat pipe 30 containing a working fluid therein and transferring heat through the evaporation and condensation of the working fluid; alternatively, the heat pipe 30 does not contain working fluid therein but is made of a material having a high heat conductivity through which the heat is transferred. The heat pipe according to the present invention may use either of the above-mentioned methods.

Further, solder paste or thermal grease may be used as the adhesive. The adhesive is applied between the groove 21 of the heat conducting plate 20 and the coupling part 31 of the heat pipe 30 so as to prevent an empty space from being created between the groove 21 and the coupling part 31, thus improving the heat conductivity of the heat conducting plate and the heat pipe. Further, the adhesive is hardened through a reflow process in order to more firmly couple the heat conducting plate 20 with the heat pipe 30.

As shown in FIG. 1, the cooling unit 40 has the shape of a fin and serves to dissipate heat transmitted through the heat pipe 30 to the outside. The cooling unit 40 is not limited to the shape of the fin shown in FIG. 1, and may further include a cooling fan.

The heat conducting plate according to the preferred embodiment of the present invention will be described in detail with reference to FIG. 2.

As shown in FIG. 2, the heat conducting plate 20 has the groove 21 which has the shape of an internal thread.

The groove 21 may be formed to pass from one side in a thickness direction of the heat conducting plate 20 to the center thereof. The groove 21 is the area into which the coupling part 31 of the heat pipe 30 that will be described below in detail is inserted in a screw-type coupling manner.

The groove 21 may be formed to pass through part of the heat conducting plate 20 in the direction of the center thereof. However, in order to increase the contact area of the heat pipe 30 with the heat conducting plate 20, the groove 21 is preferably formed to completely pass from one side to the other side in the thickness direction of the heat conducting plate 20.

Further, the groove 21 has the shape of the internal thread. In this regard, the shape of the internal thread means the shape in which threads are formed on the inner surface of the groove. Such a shape allows the heat pipe 30 with the coupling part 31 having the shape of an external thread to be more firmly coupled to the heat conducting plate 20 using the screw-type coupling manner.

Preferably, the pitch, depth and shape of the internal thread correspond to those of the external thread so that the internal thread of the groove 21 easily engages with the external thread of the coupling part 31 of the heat pipe 30.

The heat pipe according to the preferred embodiment of the present invention will be described in detail with reference to FIG. 3.

As shown in FIG. 3, the heat pipe 30 has the coupling part 31 having the shape of the external thread.

The coupling part 31 is provided on a predetermined portion of the heat pipe 30. Preferably, the length of the coupling part 31 corresponds to that of the groove 21 of the heat conducting plate 20. Further, the coupling part 31 may be provided on the middle portion of the heat pipe 30. However, it is preferable that the coupling part 31 be formed from a central portion of the heat pipe 30 to an end thereof. Such a construction enables the position of the heat pipe 30 relative to the heat conducting plate 20 to be adjusted.

Further, the coupling part 31 has the shape of the external thread. The shape of the external thread means the shape in which threads are formed on the outer surface of the pipe.

Here, the groove 21 of the heat conducting plate 20 is coupled to the coupling part 31 of the heat pipe 30 in a screw-type coupling manner, so that the frequency of cracks which may occur during coupling is reduced unlike a simple coupling manner which uses press fitting, and the contact area of the groove 21 with the coupling part 31 is increased. Consequently, heat conductivity is improved.

Meanwhile, the external thread may have various shapes including a triangular thread, a square thread, and a buttress thread. The external thread preferably comprises a round thread which enables the groove 21 to be coupled with the coupling part 31 in a screw-type coupling manner without generating friction, in addition to increasing a contact surface.

FIG. 4 is a sectional view taken along line A-A′ of FIG. 1 and illustrating a heat conducting plate according to another preferred embodiment of the present invention, FIG. 5 is a perspective view illustrating a heat pipe which is to be coupled to the heat conducting plate in a screw-type coupling manner, and FIG. 6 is a sectional view illustrating a shape in which the heat pipe is coupled to a groove of the heat conducting plate.

Hereinafter, a radiating package module for an exothermic element according to to another embodiment of the present invention will be described with reference to FIGS. 4 to 6. The detailed description of the construction of the radiating package of FIGS. 4 to 6 which is equal to that of the radiating package of FIGS. 1 to 3 will be omitted herein.

The heat conducting plate according to the preferred embodiment of the present invention will be described in detail with reference to FIG. 4.

Here, the heat conducting plate 20 has a groove 21 having the shape of an internal thread. A micro pattern 22 is further provided on a surface of the internal thread.

The micro pattern 22 is a micro groove which is formed at an inner position on the internal thread. Since the micro groove may have various shapes, including those of a triangle, a square, and a circle, the shape of the micro pattern is not limited. Further, it is preferable that the micro pattern 22 be continuously formed on the surface of the internal thread in a solid line or a broken line.

As shown in FIG. 4, the micro pattern 22 is preferably formed in the same direction as the proceeding direction of the internal thread. The internal thread is formed such that a thread is positioned in a surface while having a predetermined torsion angle. If the micro pattern is formed to have the same angle as the torsion angle of the internal thread, the micro pattern may be formed in the same direction as the thread of the internal thread. Further, a plurality of micro patterns 22 may be formed on one thread by adjusting the width of a micro pattern 22 and an interval between adjacent micro patterns 22.

Meanwhile, the micro pattern 22 may be formed through mechanical etching, and is covered by an adhesive containing a polymer core when the coupling part 31 of the heat pipe 30 is coupled to the groove 21. When the micro pattern 22 is covered by the adhesive, heat conductivity is improved. The groove 21 of the heat conducting plate 20 is more strongly coupled to the coupling part 31 of the heat pipe 30.

Further, when the coupling part 31 of the heat pipe 30 having the shape of the external thread is coupled to the groove 21 in a screw-type coupling manner, the adhesive and the polymer core (not shown) are naturally inserted into the micro pattern 22.

The polymer core may be a spherical particle which includes a core made of polymer and a contact layer surrounding the core. Since the core is made of polymer, stress relief ability is excellent. Further, since the contact layer comprises a metal plating layer, it has heat conductivity. The type of polymer forming the core and the metal plating layer is not subject to any specific limitations. However, the contact layer is preferably made of gold or nickel having high heat conductivity.

Further, the diameter of the polymer core is not limited, and polymer cores of a variety of sizes may be applied to this embodiment. In order to allow the polymer core to be inserted into the micro pattern 22, the polymer core which has a size corresponding to that of the micro pattern is preferably used.

Therefore, the polymer core is inserted into the micro pattern 22, so that heat conductivity for transferring heat from the heat conducting plate 20 to the heat pipe 30 is maintained, and a crack occurring in the heat conducting plate 20 changes its proceeding direction or is delayed when the crack proceeds to the surface of the internal thread, and so that impacts continuously acting on the heat conducting plate 20 are absorbed by the polymer core. As a result, the progress of a crack can be delayed.

The heat pipe according to the preferred embodiment of the present invention will be described in detail with reference to FIG. 5.

The heat pipe 30 has a coupling part 31 having the shape of an external thread, and a micro pattern 32 formed on a surface of the external thread.

The micro pattern 32 formed on the surface of the external thread has the same shape as the micro pattern 22 of the groove 21 which is formed on the heat conducting plate 20, and may be formed in the same manner as the micro pattern 22 of the groove 21. Further, polymer core may be inserted into the micro pattern 32 formed on the surface of the external thread of the coupling part 31, in the same manner that the polymer core is inserted into the micro pattern 22 of the groove 21.

The polymer core changes the direction in which a crack proceeds when one occurs in the heat pipe 30 or delays the crack, and absorbs impact acting on the heat pipe 30.

Meanwhile, since the micro pattern 22 formed on the surface of the internal thread and the micro pattern 32 formed on the surface of the external thread may be made through separate mechanical etching, the micro patterns may have different shapes. Although the micro patterns 22 and 32 have different shapes, it is preferable that each micro pattern be formed in the same direction as the thread, as described above with reference to FIG. 4.

FIG. 6 is a sectional view illustrating the shape in which the coupling part 31 of the heat pipe 30 is coupled to the groove 21 of the heat conducting plate 20 in a screw-type coupling manner. The shape of the groove 21 coupled with the coupling part 31 will be described below with reference to FIG. 6.

Both the groove 21 and the coupling part 31 may be formed to have micro patterns on surfaces thereof. That is, the first micro pattern 22 is formed on the surface of the groove 21, and the second micro pattern 32 is formed on the surface of the coupling part 31. Here, polymer cores may be inserted, respectively, into the first micro pattern 22 and the second micro pattern 32 to be secured thereto.

Meanwhile, a polymer core 51 may be placed between the surface of the coupling part 31 having no micro pattern and the surface of the groove 21 having no micro pattern, thus maintaining stress relief ability, therefore reducing impact acting on the radiating package.

Further, as shown in FIG. 6, the first micro pattern 22 or the second micro pattern 32 is formed in the same direction as a thread. The first and second micro patterns 22 and 32 may be formed at corresponding positions. Thus, the polymer core 51 may be positioned between the micro patterns 22 and 32.

Since the polymer core 51 is uniformly inserted between the micro patterns 22 and 32, it can delay a crack occurring in the groove 21 or the coupling part 31 and mitigate impact acting on the radiating package.

Meanwhile, FIG. 6 shows an example provided merely for illustrative purposes wherein three micro patterns 32 are formed on a unit thread of the coupling part 31. Further, the degree of etching changes according to the size of the polymer core 51 contained in the adhesive 50 so as to adjust the size of the micro pattern 32.

As described above, the present invention provides a radiating package module for an exothermic element, which uses a screw-type coupling method in place of a simple coupling method of forced press-fitting, thus changing the structural shape thereof and thereby improving the structural reliability of the radiating package.

Further, the present invention provides a radiating package module for an exothermic element, in which an adhesive containing a polymer core is applied between a heat conducting plate and a heat pipe so as to prevent thermal resistance from being generated between radiation parts, thus maintaining heat transfer characteristics and improving the structural reliability of the radiating package.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Accordingly, such modifications, additions and substitutions should also be understood as falling within the scope of the present invention. 

1. A radiating package module for an exothermic element, comprising: a heat conducting plate having a groove of an internal thread shape, with the exothermic element being mounted on a surface of the heat conducting plate; a heat pipe inserted into the groove in a screw-type coupling manner, and having a coupling part of an external thread shape; an adhesive applied between the groove and the coupling part; and a cooling unit coupled to an end of the heat pipe.
 2. The radiating package module as set forth in claim 1, wherein the groove passes from a side of the heat conducting plate to an opposite side thereof.
 3. The radiating package module as set forth in claim 1, wherein the coupling part has a shape of a round thread.
 4. A radiating package module for an exothermic element, comprising: a heat conducting plate having a groove of an internal thread shape, with the exothermic element being mounted on a surface of the heat conducting plate; a heat pipe inserted into the groove in a screw-type coupling manner, and having a coupling part of an external thread shape; an adhesive applied between the groove and the coupling part; a polymer core contained in the adhesive; and a cooling unit coupled to an end of the heat pipe, wherein a micro pattern is formed on either of a surface of the groove or a surface of the coupling part.
 5. The radiating package module as set forth in claim 4, wherein the micro pattern is formed in the same direction as the thread.
 6. A radiating package module for an exothermic element, comprising: a heat conducting plate having the exothermic element mounted on a surface thereof and a groove of an internal thread shape, with a first micro pattern being formed on a surface of the groove; a heat pipe inserted into the groove in a screw-type coupling manner, and having a coupling part of an external thread shape, with a second micro pattern being formed on a surface of the coupling part; an adhesive applied between the groove and the coupling part; a polymer core contained in the adhesive; and a cooling unit coupled to an end of the heat pipe.
 7. The radiating package module as set forth in claim 6, wherein the first micro pattern and the second micro pattern are formed in the same directions as the internal thread and the external thread, respectively, the first micro pattern and the second micro pattern being formed at corresponding positions. 